<h2 mat-dialog-title>Type your email:</h2>
<p class="error" *ngIf="shouldShowError">{{error}}</p>
<mat-dialog-content [formGroup]="form">
  <mat-form-field>
    <input matInput placeholder="Subject" formControlName="subject" required>
  </mat-form-field>
  <mat-form-field>
    <input matInput placeholder="Content" formControlName="content" required>
  </mat-form-field>
</mat-dialog-content>
<mat-dialog-actions>
  <button mat-button (click)="cancel()">Cancel</button>
  <button mat-button (click)="submit()" [disabled]="form.invalid">Send</button>
</mat-dialog-actions>
